New blood test may let food allergy suspect off the hook

AllerGen researchers, together with collaborators at Harvard Medical School, have demonstrated that an immune cell previously thought to be involved in maintaining lifelong food allergies is likely not the culprit after all.

The research, published in the Journal of Allergy and Clinical Immunology, found that IgE+ memory B cells are extremely rare in the blood of food-allergic individuals, which, in turn, suggests that these cells are likely not responsible for how the immune system “remembers” food allergens.

To enable this discovery, the researchers developed a novel, cutting-edge technique for blood analysis, which entails genetic analysis at the single-cell level.

“Previous research has proposed that upon re-encountering a food allergen, IgE+ memory B cells become activated and replenish the cells that produce IgE antibodies, which ultimately triggers an allergic reaction; however, no one has been able to decipher how the IgE memory works,” said lead researcher Dr. Manel Jordana (McMaster University).

“Our study has shown the extreme rarity of IgE+ memory B cells in the blood of food-allergic patients, suggesting that the presence of these cells is neither a predictor of allergy nor what maintains it.”

Also on the research team were AllerGen investigator Dr. Susan Waserman, AllerGen HQP Dr. Rodrigo Jiménez-Saiz, graduate student Kelly Bruton, and medical students Yosef Ellenbogen and Paul Spill, all at McMaster University, along with Drs Wayne Shreffler and Sarita Patil at Harvard Medical School.